Lab Preparation of Carbon Dioxide (CO■)
Principle:
CaCO■ + 2HCl → CaCl■ + H■O + CO■↑
Apparatus:
Conical flask, thistle funnel, delivery tube, drying tube (optional), gas jars, trough.
Chemicals Required:
Marble chips (CaCO■) or NaHCO■, dilute HCl, anhydrous CaCl■, limewater.
Procedure:
1. Place marble chips in the flask. 2. Add dilute HCl via thistle funnel. 3. Collect CO■ by downward
delivery into a gas jar. 4. Test with limewater.
Test:
Limewater turns milky. Extinguishes flame. Turns moist blue litmus red.
Precautions:
Use dilute acid. Prevent suck-back. Ensure airtight setup. Do not inhale gas.
Physical Properties:
Colourless, odourless, denser than air, slightly soluble in water, non-combustible.
Chemical Properties:
• With bases: NaOH + CO■ → Na■CO■ • With oxides: CaO + CO■ → CaCO■ • With Mg (hot):
2Mg + CO■ → 2MgO + C
Uses:
Fire extinguishers, carbonation of drinks, dry ice for cooling, greenhouses, inert atmosphere.
Principle:
CaCO■ + 2HCl → CaCl■ + H■O + CO■↑
Apparatus:
Conical flask, thistle funnel, delivery tube, drying tube (optional), gas jars, trough.
Chemicals Required:
Marble chips (CaCO■) or NaHCO■, dilute HCl, anhydrous CaCl■, limewater.
Procedure:
1. Place marble chips in the flask. 2. Add dilute HCl via thistle funnel. 3. Collect CO■ by downward
delivery into a gas jar. 4. Test with limewater.
Test:
Limewater turns milky. Extinguishes flame. Turns moist blue litmus red.
Precautions:
Use dilute acid. Prevent suck-back. Ensure airtight setup. Do not inhale gas.
Physical Properties:
Colourless, odourless, denser than air, slightly soluble in water, non-combustible.
Chemical Properties:
• With bases: NaOH + CO■ → Na■CO■ • With oxides: CaO + CO■ → CaCO■ • With Mg (hot):
2Mg + CO■ → 2MgO + C
Uses:
Fire extinguishers, carbonation of drinks, dry ice for cooling, greenhouses, inert atmosphere.
